@phaserjs/phaser/geom/triangle/GetTriangleEdges.js

Phaser 4

import { Line } from "../line/Line";
export function GetTriangleEdges(triangle) {
  const { x1, y1, x2, y2, x3, y3 } = triangle;
  const edge1 = new Line(x1, y1, x2, y2);
  const edge2 = new Line(x2, y2, x3, y3);
  const edge3 = new Line(x3, y3, x1, y1);
  return [edge1, edge2, edge3];
}